Silent letters are letters that appear in the spelling of a word but are not pronounced, such as the k in knife, the b in comb and the w in write. Most come from older pronunciations, so they follow patterns you can learn, but a dictionary is always the final check.
What are silent letters?
In English, the spelling and the sound of a word do not always match. A silent letter is one that is written but not said. You see k in knee, but you say /niː/. You see b in thumb, but you say /θʌm/.
Many silent letters were pronounced hundreds of years ago. The spelling stayed the same while the speech changed. This is why the system looks random, even though it is often not. Several patterns cover many of the common words.
The most useful patterns
Learn these patterns first. They cover words that you will meet in IELTS reading and speaking.
- kn- at the start: the k is silent. Know, knife, knee, knock, knowledge.
- wr- at the start: the w is silent. Write, wrong, wrap, wrist, wrinkle.
- -mb at the end: the b is silent. Comb, climb, thumb, bomb, lamb, plumber.
- -gn at the end or before an ending: the g is silent. Sign, design, foreign, reign, campaign.
- -stle, -sten and -ften in the middle: the t is silent. Castle, whistle, listen, fasten, soften.
- gh in -ght and -igh: the gh is silent. Night, light, high, daughter, thought.
- h at the start of a few words: hour, honest, honour, heir.
- l before k, f or m in some words: talk, walk, half, calm, palm, salmon.
Other common ones to know
Some silent letters have no clear pattern, so learn them as individual words. The p is silent in psychology, receipt and cupboard. The n is silent after m at the end of autumn, column and damn. The s is silent in island and aisle. The d is silent in Wednesday /ˈwenzdeɪ/ and handsome. The u is silent after g in guess, guitar and guard.
Some words lose a whole sound or in everyday speech, such as different /ˈdɪfrənt/, vegetable /ˈvedʒtəbl/, comfortable /ˈkʌmftəbl/ and interesting /ˈɪntrəstɪŋ/. In these words, the e or the is not said. A good dictionary shows these shortened forms.
Not silent in some words
A letter can be silent in one word and sounded in another. The t is silent in listen, but it is said in lesson. The b is silent in bomb, but it is said in bombard. In the word often, some people say the t and others do not, so both are acceptable.
The letter r is a special case in British English. It is silent when it comes after a at the end of a word or before a , as in car and park. It is said before a vowel, as in red and very, and it can appear in links such as 'far away'.
A method for learning them
Do not try to memorise a long list. Use a small routine. When you meet a new word, check its sound in a dictionary. If a letter is silent, mark it with a line in your notebook, and write the sound next to the word. Group the words by pattern, such as the kn- words on one page and the -mb words on another.
Say the words aloud, quickly, and then say them in a sentence of your own: 'I know a wrong answer when I hear one.' 'We climbed the hill and saw a lamb.' Short, simple sentences keep the sound in your ear and mouth.
Why this matters for IELTS
In speaking, saying a silent letter can confuse the listener. Learners who say the k in knife or the b in climb may be understood, but the word may sound unusual. The wrong or sound can make a common word hard to recognise.
In writing, the opposite problem appears. Because you do not hear the letter, you may leave it out when you spell. Words like foreign, knowledge, answer and island are common in IELTS essays, and a missing silent letter is a spelling mistake. Learning the pattern helps both skills.
Who finds this hard?
- Spanish speakers: Spanish spelling is close to its sounds, so Spanish speakers often say every written letter in English. Words like knife, climb and island are typical examples.
- Italian speakers: Italian spelling is also close to sound, so learners often pronounce the k in knee or the b in comb. Check each new word in a dictionary.
- Turkish speakers: Turkish spelling matches its sounds very closely, so silent letters in English are a new idea. Learn the patterns and practise the words aloud.
IELTS tip
In the Speaking test, check the sound of a few important words from your topics, such as foreign, knowledge, answer and island, and say them aloud without the silent letters. In the Writing test, silent letters are a common source of spelling errors, so write a short list of the ones you often forget and check it before you finish an essay.
Frequently asked questions
Why does English have silent letters?
Many were pronounced in the past, but speech changed while spelling stayed the same. Others came from the spelling of words borrowed from other languages.
What is the most common silent letter?
The final e is one of the most common silent letters, as in make and hope. Other very common ones are the k in kn- words, the w in wr- words, the b in -mb words and the h in hour and honest.
How can I know if a letter is silent?
Check the pronunciation in a dictionary. It shows the sounds between slashes, and a silent letter will not appear there. Learn the common patterns too.
Is the t in often silent?
Both pronunciations are used in British English: /ˈɒfn/ and /ˈɒftən/. Either is fine, so choose one and use it consistently.
Sources
- Roach, P., Setter, J., & Esling, J. (Eds.). (2011). Cambridge English Pronouncing Dictionary (18th ed.). Cambridge University Press.
- Wells, J. C. (2008). Longman Pronunciation Dictionary (3rd ed.). Pearson Longman.